I found that Office Depot is a great place to find inexpensive paper, crayons, school glue, markers, etc. The very best time to get these things is in August, when parents are preparing for the school year. One year we got about 40 packs of 200 count lined notebook paper - it lasted us for 2 whole years, and the paper was something like 25 cents a pack.

Other great places for school supplies for a large family are Costco, and places like Big Lots.

One of my children is an origami artist. So, we go through lots and lots of paper here!